A joint Fermilab/SLAC publication
INFN

OPERA snags third tau neutrino

03/26/13

For the third time since the OPERA detector began receiving beam in 2006, the experiment has caught a muon neutrino oscillating into a tau neutrino.

For the third time ever, scientists have seen the particle transformation that explains the mystery of the “missing neutrinos”—particles we expect to rain down from the Sun and Earth’s atmosphere at higher rates than observed.

Neutrinos are light particles that come in three types, or flavors, each associated with a different subatomic particle: an electron, a muon or a tau. One of the biggest surprises that came with the discovery of neutrinos was that they could change from flavor to flavor.

Members of the OPERA experiment announced today the observation of a muon neutrino that had switched flavors to a tau neutrino. OPERA scientists, based at Gran Sasso National Laboratory in Italy, have caught this rare event only twice before, once in 2010 and once in 2012. 

The new observation “is an important confirmation of the two previous observations,” says Giovanni De Lellis, head of the international research team, in a statement released by INFN.

The OPERA experiment is a fast-moving, long-distance game of catch, with CERN laboratory at the border of France and Switzerland pitching a concentrated beam of neutrinos toward the 1,250-ton OPERA detector. The neutrino is a difficult ball to snag; it interacts so rarely with matter that it can zip unflinchingly through an entire planet. 

The OPERA experiment is the first neutrino experiment to examine a manmade beam of muon neutrinos in search of this type of oscillation. It will continue to take data for the next two years.

Latest news articles

06/27/16
Fermilab

Edwards, one of the most vital contributors to the success of Fermilab over its five-decade history, died on June 21 at the age of 80.

06/17/16
CERN

For the first time a beam of particles has been sent through the Advanced Proton Driven Plasma Wakefield Acceleration Experiment.

06/15/16

Second gravitational wave detection announced

For a second time, scientists from the LIGO and Virgo collaborations saw gravitational waves from the merger of two black holes.

06/13/16

CERN grants beam time to students

Contest winners will study special relativity and an Egyptian pyramid using a CERN beamline.